New to me Lenco B55

[doucanoe]

New to me in more ways than one seeing as how I have never restored a turntable before.

I realize that the B55 isn't the ideal Lenco candidate for a complete full blown project, but I'm looking forward to learning from it. I think I'm going to be spending my fair share of time here reading the "How To" section for a while.

Not trying to get too far ahead of myself here but I do have a question. I'm looking at it arm (original) and am curious to get opinions on it. Is the B55 worthy of investing in a new more substantial tonearm?

Any sage words of advice from individuals who have worked on the B55 would be greatly appreciated also.

RC

[Redboy]

I'll be watching this one closely, too.  I want you to build a massive plinth of some sort, Ron!   

[doucanoe]

I'll be watching this one closely, too.  I want you to build a massive plinth of some sort, Ron!  

It would be cool to do that but I'm wondering if it's worth the effort for a B55.

I was reading the thread in How to regarding a built up plinth for the L75 using Baltic Birch or similar. What I don't understand and never have actually, is why are the cut outs of different size. I understand that as you get lower in the build up there is less and less mechanism but why not just make everything after the second tier down the same?


Is it just a "mass" thing?

RC

[GP49]

I was reading the thread in How to regarding a built up plinth for the L75 using Baltic Birch or similar. What I don't understand and never have actually, is why are the cut outs of different size. I understand that as you get lower in the build up there is less and less mechanism but why not just make everything after the second tier down the same?

Is it just a "mass" thing?

That's the idea if you are building a mass-loaded plinth.  Make the cutouts as small as possible, to maximize mass.  When I built mine I made a pattern for each level, one-by-one.

[Steve]

It would be cool to do that but I'm wondering if it's worth the effort for a B55.

I was reading the thread in How to regarding a built up plinth for the L75 using Baltic Birch or similar. What I don't understand and never have actually, is why are the cut outs of different size. I understand that as you get lower in the build up there is less and less mechanism but why not just make everything after the second tier down the same?


Is it just a "mass" thing?

RC

Hi Ron,

The KISS philosophy has proven itself over time to be a winner when it comes to reliable design.  My limited experience in the realm of plinths leads me to believe that mass does play a large role in sinking unwanted vibration away from the delicates.  Heavy doesn't hurt.  That said, there certainly is more to it than just dampening spurious noise.  If it were only about dampening, then a phone book might make a nice plinth.   

I know that slate's popular, and for good reason.  But wood is good too.  And it waaaay easier to cut...I'm looking forward to having a look, and maybe a listen.

Best,
Steve

[Redboy]

Earlier today I offered Ron a Linn LVX (or is it LXV?) tonearm that I have - can someone confirm that this would be a drop-in replacement for the B55, like it is for the L78?

[mfrench]

It would be cool to do that but I'm wondering if it's worth the effort for a B55.

I was reading the thread in How to regarding a built up plinth for the L75 using Baltic Birch or similar. What I don't understand and never have actually, is why are the cut outs of different size. I understand that as you get lower in the build up there is less and less mechanism but why not just make everything after the second tier down the same?


Is it just a "mass" thing?

RC

Yes, its a mass thing, and, for contouring to the 3D contour levels of mechanisms below the top plate. The speed movements occupy a certain depth and space, the bearing a bit more depth, and the motor is at another depth. You want as much solid mass as possible, to support the top plate, and the bearing, to keep the top plate and bearing rigid, non-flexing.
You can quit contouring for the speed mechanisms sooner than the bearing, and eventually you're left with motor depth, which goes all the way through for ventilation.

[d to the g]

congrats on the new deck Ron!

Earlier today I offered Ron a Linn LVX (or is it LXV?) tonearm that I have - can someone confirm that this would be a drop-in replacement for the B55, like it is for the L78?

From the owners manual, the L69:
Total arm length: 9 3/8"
Mounting distance: 8 1/4"
Overhang of stylus: 5/8"
Total adjustment of overhang: 1/2"

Whereas the 75 arm...
Mounting distance: 8.3"
Overhang: 0.675"

The Linn is actually specified as 211mm (8.31"), and only 9" effective length, you might end up having to use a slightly different alignment but looks to be worth trying.

edit: From Born in 50's site: " L69 arm hole is smaller than the L75 so no way to mount a Linn arm without surgery."

[doucanoe]

Well I tell you what, guys. After reading through a few things here it sure looks like I have some work to do first.

I can see that a built up plinth even if it's out of non-void material, might be reasonable and certainly not difficult to cut/machine.  I think I best save the Slate or Fossil Shale plinth for if and when I elevate myself from rookie status 


As Nate mentioned, we discussed the arm issue briefly earlier today. That may be in the mix also.

Thanks for the input and even though this is going to be a slow process, I'll keep everyone posted.

[Redboy]

edit: From Born in 50's site: " L69 arm hole is smaller than the L75 so no way to mount a Linn arm without surgery."

Hmm, rats.  We'll have to experiment a bit with this, maybe. 

Thanks for the info, Doug! 

[colin]

Hi Ron,

Your B55 was available in the UK as the GL72, here is a page about one of mine. 

http://bornin50.webs.com/gl72.htm

The flat deckplate makes it easier to make the first layer with plenty of wood to metal contact - search for B55 or B52 or GL69 or GL72 here at LH - they are all pretty much the same thing.

The arm is the same geometry as the 75 arm, but as mentioned the collar is smaller on the B55.  Lenco arms polarise folks according to how much work you want to do - my take is the arm is ok for carts that track at 2gms or more. 

A Linn arm will fit with some drilling and is a definite step in the right direction - the higher platter surface means no problem using the Linn collar.

The B55 is probably the best Lenco to start off with, make the plinth, get it running fine and it is a great player.  A simple filing and drilling operation will allow you to fit the heavy platter and bearing - running with the big dogs now!  My projects tend to stop around the time the deck works, so not much happens in the good-look stakes, here's a Lencostein - the end of the line for the deck in the previous link -

http://www.freewebs.com/bornin50-4/newlencostein.htm

 

[doucanoe]

congrats on the new deck Ron!

From the owners manual, the L69:
Total arm length: 9 3/8"
Mounting distance: 8 1/4"
Overhang of stylus: 5/8"
Total adjustment of overhang: 1/2"

Whereas the 75 arm...
Mounting distance: 8.3"
Overhang: 0.675"

The Linn is actually specified as 211mm (8.31"), and only 9" effective length, you might end up having to use a slightly different alignment but looks to be worth trying.

edit: From Born in 50's site: " L69 arm hole is smaller than the L75 so no way to mount a Linn arm without surgery."

Thanks Doug!

I can see that modifying the arm hole may be in order then. I'm looking at the original arm and am really thinking that I would like to run with something a bit more substantial (within reason of course). I would assume that any modification to the arm hole could be consealed with the addition of a arm board plate. The anti skate from the original arm would be lost in the process anyway so there would be no point in trying to keep it cosmetically original.

[doucanoe]

Hi Ron,

Your B55 was available in the UK as the GL72, here is a page about one of mine. 

http://bornin50.webs.com/gl72.htm

The flat deckplate makes it easier to make the first layer with plenty of wood to metal contact - search for B55 or B52 or GL69 or GL72 here at LH - they are all pretty much the same thing.

The arm is the same geometry as the 75 arm, but as mentioned the collar is smaller on the B55.  Lenco arms polarise folks according to how much work you want to do - my take is the arm is ok for carts that track at 2gms or more. 

A Linn arm will fit with some drilling and is a definite step in the right direction - the higher platter surface means no problem using the Linn collar.

The B55 is probably the best Lenco to start off with, make the plinth, get it running fine and it is a great player.  A simple filing and drilling operation will allow you to fit the heavy platter and bearing - running with the big dogs now!  My projects tend to stop around the time the deck works, so not much happens in the good-look stakes, here's a Lencostein - the end of the line for the deck in the previous link -

http://www.freewebs.com/bornin50-4/newlencostein.htm

 

Thanks for the info. and links Colin.

All this is going to be very helpful as I formulate a plan.

[doucanoe]

Here is what I am starting with for documentation sake.

[d to the g]

Ron, that decks looks nice!

A Linn arm will fit with some drilling and is a definite step in the right direction - the higher platter surface means no problem using the Linn collar.

Personally, I'd skip the drill and use a chassis punch with the centering method described in Morgan Jone's book.

(That whole finger thing has made me think twice about how I get the job done)